On Fri, 2016-11-04 at 18:51 +0100, Bernd Schmidt wrote:
> Here's something simpler. Only very lightly tested, but isn't
> something
> like this all that's needed? Could decide whether to apply it to
> expr_list etc. as well.
>
> Index: print-rtl.c
> ===================================================================
> --- print-rtl.c (revision 241233)
> +++ print-rtl.c (working copy)
> @@ -697,7 +697,12 @@ print_rtx (const_rtx in_rtx)
>
> /* Get the format string and skip the first elements if we have
> handled
> them already. */
> - for (; idx < GET_RTX_LENGTH (GET_CODE (in_rtx)); idx++)
> + int limit = GET_RTX_LENGTH (GET_CODE (in_rtx));
> + if (flag_compact
(as of r241586 this is now "m_compact")
> + && INSN_CHAIN_CODE_P (GET_CODE (in_rtx))
> + && XEXP (in_rtx, limit - 1) == NULL_RTX)
> + limit--;
> + for (; idx < limit; idx++)
> print_rtx_operand (in_rtx, idx);
>
> switch (GET_CODE (in_rtx))
Thanks.
This seems to assume that the final code in the fmt string can be
accessed via XEXP (in_rtx, limit - 1), which if RTL checking is
enabled requires that the code be either 'e' or 'u'.
This isn't the case for JUMP_INSN, JUMP_TABLE_DATA, BARRIER
(all code '0'), CODE_LABEL (code 's') and NOTE (code 'i').
Also, we might want to omit the REG_NOTES from, say a JUMP_INSN, which
is the *penultimate* operand - for example, it doesn't omit the
trailing (nil) from the cjump_insn in test_uncond_jump.
That said, this is much simpler than my patch, so I used it as the
basis for the following: it uses the same approach as your patch, but
loops backwards from the end of the format string (rather than just once)
until it finds a non-default value, using a new function
"operand_has_default_value_p" to handle the logic for that.
With this, compact dumps omit the trailing (nil) for both regular insns
and for JUMP_INSNs, and omits the surplus newline seen in my earlier patch.
It also appears removes the trailing (nil) from expr_list.
Bootstrap®rtest in progress.
OK for trunk if it passes?
gcc/ChangeLog:
* print-rtl.c (operand_has_default_value_p): New function.
(rtx_writer::print_rtx): In compact mode, omit trailing operands
that have the default values.
* rtl-tests.c (selftest::test_dumping_insns): Remove empty
label string from expected dump.
(seltest::test_uncond_jump): Remove trailing "(nil)" for REG_NOTES
from expected dump.
---
gcc/print-rtl.c | 45 ++++++++++++++++++++++++++++++++++++++++++++-
gcc/rtl-tests.c | 5 ++---
2 files changed, 46 insertions(+), 4 deletions(-)
diff --git a/gcc/print-rtl.c b/gcc/print-rtl.c
index 341ecdf..493aa68 100644
--- a/gcc/print-rtl.c
+++ b/gcc/print-rtl.c
@@ -564,6 +564,40 @@ rtx_writer::print_rtx_operand (const_rtx in_rtx, int idx)
}
}
+/* Subroutine of rtx_writer::print_rtx.
+ In compact mode, determine if operand IDX of IN_RTX is interesting
+ to dump, or (if in a trailing position) it can be omitted. */
+
+static bool
+operand_has_default_value_p (const_rtx in_rtx, int idx)
+{
+ const char *format_ptr = GET_RTX_FORMAT (GET_CODE (in_rtx));
+
+ switch (format_ptr[idx])
+ {
+ case 'e':
+ case 'u':
+ return XEXP (in_rtx, idx) == NULL_RTX;
+
+ case 's':
+ return XSTR (in_rtx, idx) == NULL;
+
+ case '0':
+ switch (GET_CODE (in_rtx))
+ {
+ case JUMP_INSN:
+ return JUMP_LABEL (in_rtx) == NULL_RTX;
+
+ default:
+ return false;
+
+ }
+
+ default:
+ return false;
+ }
+}
+
/* Print IN_RTX onto m_outfile. This is the recursive part of printing. */
void
@@ -681,9 +715,18 @@ rtx_writer::print_rtx (const_rtx in_rtx)
fprintf (m_outfile, " %d", INSN_UID (in_rtx));
}
+ /* Determine which is the final operand to print.
+ In compact mode, skip trailing operands that have the default values
+ e.g. trailing "(nil)" values. */
+ int limit = GET_RTX_LENGTH (GET_CODE (in_rtx));
+ if (m_compact)
+ while (limit > idx && operand_has_default_value_p (in_rtx, limit - 1))
+ limit--;
+
/* Get the format string and skip the first elements if we have handled
them already. */
- for (; idx < GET_RTX_LENGTH (GET_CODE (in_rtx)); idx++)
+
+ for (; idx < limit; idx++)
print_rtx_operand (in_rtx, idx);
switch (GET_CODE (in_rtx))
diff --git a/gcc/rtl-tests.c b/gcc/rtl-tests.c
index cf5239f..228226b 100644
--- a/gcc/rtl-tests.c
+++ b/gcc/rtl-tests.c
@@ -122,7 +122,7 @@ test_dumping_insns ()
/* Labels. */
rtx_insn *label = gen_label_rtx ();
CODE_LABEL_NUMBER (label) = 42;
- ASSERT_RTL_DUMP_EQ ("(clabel 0 42 \"\")\n", label);
+ ASSERT_RTL_DUMP_EQ ("(clabel 0 42)\n", label);
LABEL_NAME (label)= "some_label";
ASSERT_RTL_DUMP_EQ ("(clabel 0 42 (\"some_label\"))\n", label);
@@ -176,8 +176,7 @@ test_uncond_jump ()
ASSERT_TRUE (control_flow_insn_p (jump_insn));
ASSERT_RTL_DUMP_EQ ("(cjump_insn 1 (set (pc)\n"
- " (label_ref 0))\n"
- " (nil))\n",
+ " (label_ref 0)))\n",
jump_insn);
}
--
1.8.5.3
